1. Field of the Invention
The present invention relates to a novel trehalose phosphorylase, its preparation and uses, more particularly, to a novel trehalose phosphorylase which hydrolyzes trehalose in the presence of an inorganic phosphoric acid and/or its salt (hereinafter abbreviated as "inorganic phosphoric acid" throughout the present specification, if not any inconvenience will arise) to form D-glucose and .beta.-D-glucose-1-phosphoric acid and/or its salt (hereinafter abbreviated as ".beta.-D-glucose-1-phosphoric acid" throughout the present specification, if not any inconvenience will arise), and which, in reverse, forms trehalose and inorganic phosphoric acid from .beta.-D-glucose-1-phosphoric acid and D-glucose, and to the processes of the trehalose phosphorylase, saccharide compositions containing glucosyl-transferred saccharides produced by using the trehalose phosphorylase, and compositions containing the saccharide compositions.
2. Description of the Prior Art
Recently, oligosaccharides such as maltose and trehalose and functions thereof have become to be highlighted, and have been studied on their unique and different processes in view of various aspects. It is known that phosphorylases such as maltose, trehalose, sucrose, trehalose, and cellobiose phosphorylases can be used as methods for producing the above oligosaccharides.
L. R. Marechal et al reported that in "The Journal of Biological Chemistry", Vol.247, No.10, pp.3,223-3,228 (1972), Euglena gracilis produces trehalose phosphorylase intracellularly; and S. Murao et al reported that in "Agriculture and Biological Chemistry", Vol.49, No.7, pp.2,113-2,118 (1985), the properties of the enzyme. K. Aisaka et al disclosed in Japanese Patent Kokai No.59,584/95 a bacterial trehalose phosphorylase which is produced by a microorganism of the species Catellatospora ferruginea and one of the species Kineosporia aurantiaca. H. Kizawa et al reported that in "Bioscience, Biotechnology and Biochemistry", Vol.59, No.10, pp.1,908-1912 (1995), a microorganism of the species Micrococcus varians produces such an enzyme, and M. Yoshida et al reported that in "Oyo-Toshitsu-Kagaku", Vol.42, No.1, pp.19-25 (1995), a microorganism of the species Plesiomonas sp. SH-35 produces trehalose phosphorylase. Among these trehalose phosphorylases, the enzymes from the microorganisms of the species Micrococcus varians, Euglena gracilis, and Plesiomaonas sp. have lower thermal stabilities of less than 30.degree., 40.degree. and 45.degree. C., respectively, resulting both in a relatively-low reaction efficiency on an industrial scale production and in a bacterial contamination during an enzymatic reaction.